The present invention relates to apparatus for effectively utilizing the output from a magneto generator of an internal combustion engine, and more particularly to an output supply control apparatus for effectively supplying the magneto generator output to such loads as the battery, lamps and contactless ignition system of a vehicle.
In a known type of an internal combustion engine contactless ignition system of the capacitor discharge type employing an ignition capacitor charged by a magneto generator, in order to maintain the capacitor voltage substantially constant throughout a range of low to high engine speeds, a capacitor charging source includes a low-speed coil having a large number of turns of fine wire for charging the capacitor mainly at low engine speeds and a high-speed coil having a smaller number of turns of relatively heavy wire for charging the capacitor mainly at high engine speeds and the capacitor is charged directly by the output from the coils.
However, the known apparatus of the above type has the following disadvantages.
(1) The necessity for two low-speed and high-speed coils of different specifications as capacitor charging generating coils complicates the construction. Also the size is increased and the physical size of the magneto generator is increased. PA0 (2) The low-speed generating coil has a large number of turns (3,000 to 7,000 turns) of fine wire (wire diameter is 0.13 to 0.16 mm) so that the working property is deteriorated and troubles tend to occur from the quality point of view. PA0 (3) An attempt to increase the secondary voltage or the capacitor voltage at low engine speeds will also increase the secondary voltage or the capacitor voltage at intermediate and high engine speeds and thus the voltage rating of the ignition coil or the semiconductor device will become insufficient. PA0 (4) Depending on circumstances, the capacitor voltage undergoes large variations relative to the engine speeds under the effects of the capacity of the electric units, etc., with the result that the ignition signal generating circuit cannot generate a sufficient constant voltage output at low engine speeds and also the increased capacitor voltage at high engine speeds requires the use of high capacity components for voltage regulator circuit elements. PA0 (5) In addition to the generating coils forming the ignition capacitor charging source, another generating coil of a different specification must be provided separately for supplying power to another load such as the battery, with the result that not only the generator construction is complicated further but also the generating efficiency of the generator tends to be degraded.